1640444936 has 32 divisors (see below), whose sum is σ = 3314115840. Its totient is φ = 756744768.

The previous prime is 1640444921. The next prime is 1640444959. The reversal of 1640444936 is 6394440461.

It is a junction number, because it is equal to n+sod(n) for n = 1640444893 and 1640444902.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 366665 + ... + 371111.

It is an arithmetic number, because the mean of its divisors is an integer number (103566120).

Almost surely, 2^1640444936 is an apocalyptic number.

It is an amenable number.

1640444936 is an abundant number, since it is smaller than the sum of its proper divisors (1673670904).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640444936 is a wasteful number, since it uses less digits than its factorization.

1640444936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8013 (or 8009 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 41.

The square root of 1640444936 is about 40502.4065457844. The cubic root of 1640444936 is about 1179.3803449621.

The spelling of 1640444936 in words is "one billion, six hundred forty million, four hundred forty-four thousand, nine hundred thirty-six".